Drivers who are shopping the lots or looking through the car classifieds for used cars can do well to keep several basic principles in mind for guiding their choices on the used-car market and to compare used car or truck models. Here are some elementary comparisons that a driver can make for understanding which used cars may make the most sense for themselves or their household.

1. Check relative mileage - not all used cars are created equal, and many of them are priced accordingly. Some vehicle makers have a reputation for cars and trucks that can routinely run up to 200,000 miles; others create vehicles that frequently retire after 100,000 to 150,000 miles. Of course, these are general rules, but when looking at a high mileage used car, it makes sense to keep the reputation of the maker in mind.
2. Check miles per gallon - if you're buying a very used vehicle, you're not putting a lot of investment into its value, but you will still be pouring dollars into the gas tank. That's why it's a good idea for thrifty buyers of used vehicles to always be aware of the miles per gallon for the vehicle they are considering.
3. Check transmission type - your used vehicle will have either a manual (stick shift) or an automatic transmission. There are pros and cons for each transmission type. The manual is generally easier to fix, but has some vulnerability due to the clutch, and is a little harder to operate. Think about whether all of the drivers in your family will do well with a manual transmission.
4. Check engine size - again, used cars will have a wide range of engine sizes. Smaller engines get better miles per gallon, but larger engines generally offer better performance.
5. Compare features - if your used vehicle is relatively new, it probably has a lot of high-tech features that makers started putting into vehicles around the turn of the century. Power locks, seats and windows are all fine for convenience when the vehicle is new, but in a used vehicle they can break down and cause additional maintenance problems.